Aqueous Sulfite Research Articles

Photochemical transformations. XXIV. The synthesis of 18-hydroxyoestrone.

Oxidation of 17β-carbamoyloestra-1,3,5(10)-trien-3-ol methanesulphonate with lead tetra-acetate and iodine under illumination gave, on treatment with aqueous sodium hydrogen sulphite and further processing, the corresponding 18,20-anhydride. Working up with aqueous caustic alkali in dioxan afforded the 18,20-dicarboxylic acid, conveniently characterised as the dimethyl ester. By a series of more conventional reactions the anhydride, or the corresponding dimethyl ester, were transformed into 18-hydroxyoestrone diacetate and thence into 18-hydroxyoestrone.A smooth photochemical fragmentation reaction of a tertiary diphenylcarbinol nitrite has been noted.

The oxidation of aqueous sodium sulphite solutions

A method is suggested for the determination of the interfacial area between a gas and a liquid and of the surface renewal rate of this interface. This method is based upon the oxidation of a concentrated aqueous sulphite solution with gaseous oxygen in the presence of cobaltous sulphate as a catalyst. The oxidation reaction is first-order and the reaction velocity constant can be varied between 50—10,000 sec −1 by changing the catalyst concentration, the pH or the temperature. The energy of activation has been determined. The influence of some impurities and of some materials of construction has been investigated. The behaviour of copper as a catalyst is irregular; hence copper cannot be applied when the reaction is used for the determination of the contact area. Finally, some examples are given of the application of this method.

Sulfonation and inactivation of vitamin D 2 by aqueous sulfite and aeration

1. 1. Vitamin D 2 was progressively sulfonated in solutions of aqueous pyridine with or without corn oil by limited aeration in the presence of sulfite. 2. 2. The antirachitic activity of vitamin D 2 was destroyed by the self-sulfonation demonstrated.

INVESTIGATION OF VARIOUS PHYSICO-CHEMICAL FACTORS WHICH INFLUENCE SULPHITE COOKING

The penetration of aqueous sulphite solutions into differently shaped blocks of spruce wood has been investigated, the effect of the shape and type of wood, and of the presence of imprisoned air being determined. Measurements of the rates of diffusion of the constituents of calcium bisulphite solutions into pre-soaked blocks of wood showed that "free" sulphur dioxide diffused more readily than calcium bisulphite. Adsorption of sulphur dioxide and calcium bisulphite solutions by spruce wood was measured at 30° and 50 °C., and the influence of this factor on penetration was determined. The effect of penetration on delignification indicated the necessity of a satisfactory distribution of the lime salt at a low temperature to avoid localization of the lime during the pulping process.

The measurement of magnetic susceptibilities of low order : Ernest Wilson. ( Proc. Royal Soc., A680 Feb., 1920.)

The Acacia mangium tree contains 10% bark (v/v), of which about 20% are extractives. Extraction of this bark using a combination of water and sulfite medium can produce between 15% and 25% tannin materials (dry weight). In this work, several extraction conditions such as bark size, plantation site, extraction time and extraction medium were studied. The results showed that by using either hot water or a sulfite medium, a reasonable amount of tannin yield can be obtained. Bark size of less than 1-mm mesh size gave relatively high tannin yield irrespectively of the extraction medium used. Using a 600:100:2:0.5 (w/w) ratio of water:bark:sodium sulfite:sodium carbonate, and reacted at 75 °C for 3 h improved the tannin yield by at least 30%. The extracts were reasonably reactive towards formaldehyde as shown by their high Stiasny number; water extract, 60–70% and aqueous sulfite–carbonate extracts, 85–90%. The gluing results showed that the shear strength of the plywood can meet the requirements of the European Standards EN 314-1 and EN 314-2:1993. Incorporation of low molecular weight PF resin (10 parts) and PF (10 parts) improved the shear strength from 0.96 MPa to 1.43 MPa after a 72 h boiling test. This study showed that A. mangium tannin blended with commercial plywood phenol–formaldehyde resin, low molecular weight PF and paraformaldehyde as a cross-linker can be used to bond Kedondong (Canarium spp.) wood veneers suitable for both interior and exterior grade plywood.

Army ration : Dr. Merkel Nifrkll H. Jacobs, Captain, Sanitary Corps, United States Army, has studied the army ration and its balance ( Military Surgeon, 1919, xliv, G00–616)

The Acacia mangium tree contains 10% bark (v/v), of which about 20% are extractives. Extraction of this bark using a combination of water and sulfite medium can produce between 15% and 25% tannin materials (dry weight). In this work, several extraction conditions such as bark size, plantation site, extraction time and extraction medium were studied. The results showed that by using either hot water or a sulfite medium, a reasonable amount of tannin yield can be obtained. Bark size of less than 1-mm mesh size gave relatively high tannin yield irrespectively of the extraction medium used. Using a 600:100:2:0.5 (w/w) ratio of water:bark:sodium sulfite:sodium carbonate, and reacted at 75 °C for 3 h improved the tannin yield by at least 30%. The extracts were reasonably reactive towards formaldehyde as shown by their high Stiasny number; water extract, 60–70% and aqueous sulfite–carbonate extracts, 85–90%. The gluing results showed that the shear strength of the plywood can meet the requirements of the European Standards EN 314-1 and EN 314-2:1993. Incorporation of low molecular weight PF resin (10 parts) and PF (10 parts) improved the shear strength from 0.96 MPa to 1.43 MPa after a 72 h boiling test. This study showed that A. mangium tannin blended with commercial plywood phenol–formaldehyde resin, low molecular weight PF and paraformaldehyde as a cross-linker can be used to bond Kedondong (Canarium spp.) wood veneers suitable for both interior and exterior grade plywood.